What is the most crucial first aid measure for decompression sickness and arterial gas embolism?

Oxygen administration is the most crucial first aid measure for decompression sickness (DCS) and arterial gas embolism (AGE) because it directly addresses the underlying physiological issues caused by nitrogen bubbles or gas emboli in the bloodstream. In cases of decompression sickness, nitrogen that has been absorbed into tissues and blood during a dive expands and forms bubbles as a diver ascends, which can lead to severe complications.

Providing oxygen enhances tissue oxygenation and helps reduce the size of gas bubbles through a process known as the Haldane effect. This effect facilitates the elimination of nitrogen from the body by increasing the partial pressure of oxygen, thereby promoting the reabsorption of small bubbles into the bloodstream and preventing further complications.

In addition to enhancing oxygen delivery, high-flow oxygen support can help prevent hypoxia and promote healing within the affected tissues. This is pivotal in managing potential injuries from the gases released during decompression or from a gas embolism.

While fluid administration, warmth application, and compression bandaging can be supportive measures in certain situations, they do not compare to the immediate necessity of oxygen in treating the root causes of DCS and AGE. Thus, oxygen administration stands out as the essential first step in effectively managing these conditions.